<?php
/* 
 * Copyright (c) 2011 Antoine d'Otreppe de Bouvette
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

/**
 * A base that can be used for form handling 
 */
abstract class AbstractForm {
    private $namespace;
    private $fields = array();
    private $errors = array();
    
    private $defaultWidget;
    
    /**
     * @param string $namespace The namespace for the field names
     */
    public function __construct($namespace) {
        $this->namespace = $namespace;
        $this->defaultWidget = new InputWidget();
        $this->init();
    }
    
    /**
     * This method is called when the form is created to add() the fields.
     * 
     * @return void 
     */
    protected abstract function init();
    
    /**
     * Add a field to this form
     * 
     * @param string $attr
     * @param string $label
     * @param string $help
     * @param Widget $widget
     * @return AbstractForm This object, for chaining
     */
    protected function add($attr, $label, $help=null, $widget=null) {
        $widget = $widget !== null ? $widget : $this->defaultWidget;
        $item = new FormItem($this->namespace, $attr, $label, $widget, $help);
        $this->fields[$attr] = $item;
        
        return $this; // chain the calls :)
    }
    
    public function parseInto($object, Request $request) {
        $input = $request->getBodyValue($this->namespace);
        
        if ($input === null) {
            throw new RuntimeException("No such body namespace: $namespace");
        }
        
        foreach ($this->fields as $attr=>$item) {
            $raw = array_get($input, $attr, null);
            $value = $item->getWidget()->interpretInput($raw);
            $object->{'set'.ucfirst($attr)}($value);
        }
        
        return $object;
    }
    
    protected function validateProperties($object /*, $varargs */) {
        $attrs = func_get_args();
        array_shift($attrs);
        
        foreach ($attrs as $attr) {
            $method = 'validate'.ucfirst($attr);
            
            if (method_exists($object, $method)) {
                try {
                    $object->$method();
                }
                catch (UnexpectedValueException $e) {
                    $this->errors[$attr] = true;
                    $this->fields[$attr]->setError($e->getMessage());
                }
            }
        }
        
        return empty($this->errors);
    }
    
    public function fields() {
        return $this->fields;
    }
    
    public function reset() {
        $this->errors = array();
        $this->product = null;
    }
}
